This study will be open to all ACTG sites. Fifty subjects currently receiving antiretroviral therapy for at least 16 weeks, who have previously been diagnosed with DMAC, treated for at least 12 months with a macrolide- based regimen, and are asymptomatic for MAC for at least 16 weeks with CD4+ counts > or equal to 100 cells/mm3 will be eligible for entry (Step 1). All subjects will have peripheral blood cultures and a bone marrow sample (aspirate) culture performed at study entry to determine if microbiologic sterilization of MAC has occurred. If either bone marrow or blood cultures are positive for MAC, the subject will be discontinued from study, followed for survival, and receive standard of care provided by their primary care provider. If the blood and bone marrow cultures are sterile, subjects will receive 6 weeks of treatment, then discontinued MAC therapy at Week 6 entry into Step 2). Subjects will be monitored for clinical signs and symptoms of MAC and blood culture for mycobacterial will be performed according to Section 4.3. Subjects will be monitored until the last subject enrolled has been on study for approximately 60 weeks. It is anticipated that the study will accrue in approximately one year; therefore, the total duration on study for the first subject can be up to approximately 110 weeks. Peripheral blood cultures and bone marrow cultures will be obtained at any time where clinical suspicion of recurrence exists. If either or both cultures are positive, the subject will have treatment initiated at the discretion of their primary health care provider and be followed until study closure. The drugs for MAC treatment will not be provided by the study.